Folding chair with pivots in intersecting planes



May 10, 1960 H. J. KAUFMAN FOLDING CHAIR WITH PIVOTS IN INTERSECTING PLANES Filed June 27, 1957 INVENTOR.

A ORNEYS United States Patent FOLDING CHAIR WITH PIVOTS 1N INTERSECTING PLANES Hans J. Kaufman, New York, N. Y,., assignor to Stakrnore Co. Inc,, Owego, N.Y., a corporation of New York Application June 27, 1957, Serial No. 668,557

' Claims. (Cl, 155-441) This invention relates to folding chairs. It is an object of the invention to provide an improved folding chair in which different parts of the chair fold about axes that are in different planes. The construction.

results in a sturdier chair when set up; but the parts: of the chair are so connected that it can be folded and set up just as quickly and conveniently as the less stable folding chairs having all of their pivot axes parallel.

Another object of the invention is to provide a folding chair with front and back. leg assemblies connected by jointed side members that provide strong and stiff supports, but which fold horizontally and inwardly between the leg assemblies. In the preferred construction the folding of the parts is effected by swinging the seat of the chair upwardly about a hinge connection of the chair to one of the leg assemblies.

Other objects, features and advantages of the invention will appear or be pointed out as the description proceeds.

In the drawing, forming a part hereof, in which like reference characters indicate corresponding parts in all the views:

Figure l is a side elevation of a folding chair made in accordance with this invention, the chair being shown in its set-up or working position;

Figure 2 is a view similar to Figure l, but with the chair in its folded condition;

Figure 3 is a sectional view taken on the line 3-3 of Figure 1;

Figure 4 is a view similar to Figure 3 but with the chair partially folded; and

Figure 5 is a sectional view taken on the line 5-5 of Figure 2.

The chair shown in the drawing includes a front leg assembly 10 comprising front legs 11 and 12 permanently connected to a front rail 14 in accordance with conventional furniture construction. The legs 11 and 12, and the rail 14, are preferably made of wood, but other materials can be used, making it possible for the legs and rail to be one part as in a bent U out of tubing.

There is a back leg assembly 20 comprising back legs 21 and 22 permanently connected to a back rail 24, the construction being similar to that of the front leg assembly 10. The back legs 21 and 22 extend upwardly to form side frames 26 and 27 for supporting a back 30. In the preferred construction the back 30 is permanently or with a swivel connected to the side frames 26 and 27, but a swivel connection can be used and the back can be of any design desired. The legs 21 and 22, and their extensions forming the side frames 26 and 27, are curved forward so as to provide space for receiving the projecting lower end of the seat of a similar folded chair immediately behind. This makes posible the closer stacking of the chairs.

The front leg assembly 10 is connected to the back leg assembly 20 by a right-hand side member 32 and a lefthand side member 34. These side members 32 and 34 are similar except for a reversal of parts to accommodate one of them to the right side of the chair and the other to the left. A description of one of them will be sulficient for a clear understanding of both.

The side member 32 has two links 41 and 42 connected together by a joint 44, preferably a hinge. The forward link 4-1 is joined to the front assembly 10 by a pivot connection 46; and the rearward link 42 is similarlyjoined to the back leg assembly 20 by a pivot connection 48. In the construction illustrated, the joint 44 is. not at the center of the side member 32, the link 41 being somewhat longer than the link 42. This difference in the lengths of the links 41 and 42 is proportional to the difference in a the width of the leg assemblies 10 and 20'.

Parts of the side member 34 corresponding to those of the side member 32 are indicated in the drawing by the same reference characters with a prime appended.

Both of the side members 32 and 34 are of substantial height so as to be rigid in a vertical direction and capable of withstanding a heavy load. A seat 50 is connected to the front leg assembly 10 by a hinge 52. The seat rests on the back leg assembly 20 and may also rest on the side members 32 and 34.

The seat 50 extends beyond both of the leg assemblies lit and 2t and also extends beyond both of the side members 32 and 34. This construction improves. the appearance of the chair. The seat 50 is made of wood,

but other materials can be substituted, and an uphol stored seat can be used, if desired.

When the chair is to be folded, the seat 50 is swung upwardly (counter-clockwise in Figure l) about the axis of the hinge 52, and the side members 32 and 34 are folded inwardly; that is, toward one another as shown in Fig u-res 4 and 5. This folding of the side members 32 and 34 pulls the front and back leg assemblies it) and 20 together to produce the folded condition of the chair shown in Figures 2 and 5.

In order to have the folding and unfolding of the chair proceed automatically upon upward and downward swinging of the seat 50, a seat brace arm 56 is connected at its opposite ends with the seat 50 and the back leg assembly 20. The front end of the arm 56 is connected to the bottom of the seat 50 by a hinge 58; and the back end of the arm 50 has a hinge 59 connecting it to the back leg assembly 20. The way in which the raising of the seat 50 pulls the leg assemblies toward one another is apparent from an inspection of the partially raised seat 50 and the other parts indicated in broken lines in Figure 1 and a comparison of these broken-line positions with the solid-line positions of the parts in Figures 1 and 2.

When the chair is fully folded, as shown in Figure 2, it can be picked up by the upraised end of the seat 50, or by the back 30, Without any tendency for the chair to unfold. Even though the chair slopes forward when picked up by the back 39, the position of the arm 56, generally parallel to the axes of the joints and pivot connections of the side members 32 and 34, prevents the Weight of the seat 50 and its resulting down thrust on the arm 56 from producing any force components that tend to unfold the chair.

When the chair is to be unfolded, the front leg assembly 19, or the lower (hinged) end of the seat 5% is pulled forward, away from the back leg assembly 20, until the arm 56 swings into a position at an acute angle to the directions of the pivot axes of the joints and pivot connections of the side members 32 and 34. Thereafter, downward pressure on the seat 50 causes the chair to unfold further, and lock by passing through dead center.

It is a feature of the preferred construction that the links 41 and 42 are at an angle to one another when the chair is in its set-up and fully unfolded condition. The toggle joint formed by these links 41 and 42 never moves into a straight condition. It always has its joint 40 displaced inwardly. This is also true of the links 41 and 42 of the other side members 34. As a result of this construction, the side members 32 and 34 can be folded by end pressure exerted against them by the leg assemblies 10 and 20 as these leg assemblies are moved toward one another, and the chair can, therefore, be folded by the single operation of lifting the back end of the seat 50.

The preferred embodiment of the invention has been illustrated and described, but changes and modifications can be made and some features can be used. in different combinations without departing from the invention as defined in the claims.

What is claimed is:

1. A folding chair having front and back leg assemblies, means holding the front and back leg assemblies in generally parallel relation to one another while said assemblies move toward and from one another as the chair is folded and unfolded, said means including a side member at each side of the chair and hinged at its opposite ends to corresponding ends of the front and back leg assemblies with the axes of the hinge connections substantially vertical, each of the side members having a hinge joint intermediate the ends of the side member and with the axis of the hinge joint substantially parallel to the hinge connections of the side members to the front and back leg assemblies, said hinge joint constituting the side member, a toggle, and both of the toggles being flexed beyond dead center and toward one another when the chair is unfolded, a seat hinged to one of the leg assemblies on a transversely-extending horizontal axis, and a link pivotally connected at one end to the other leg assembly, and having a pivotal connection at its other end to the seat for pulling the leg assemblies together 4 and folding the toggles, said link being of a length to hold the leg assemblies spaced and the toggles bent inward and toward one another when the seat is in a lowered horizontal position whereby lifting of the unpivoted end of the seat causes the side members to fold inwardly and the chair to assume its folded condition.

2. The folding chair described in claim 1 and in which the seat, with the chair in set-up position, extends beyond the front leg assembly and beyond at least a portion of each of the side members.

3. The folding chair described in claim 2 and in which the seat also extends over at least a portion of the back leg assembly and the back of the seat rests upon said leg assembly.

4. The folding chair described in claim 3 and in which the bottom of the seat is close to the top of the side members when the chair is in its unfolded set-up condition, and the side members support the seat.

5. The folding chair described in claim 1 and in which the hinge and the pivot connections of the seat and link are so placed as to cause the pivotal connection of the link to the seat to pass across a center line connecting the axis of the seat hinge and the axis of the pivot connection of the link to the leg assembly as the chair is shifted between folded and unfolded conditions.

References Cited in the file of this patent UNITED STATES PATENTS 214,174 Morse Apr. 8, l879 2,538,637 Wilkinson Jan. 16, 1951 FOREIGN PATENTS 332,782 Great Britain July 31, 1930 516,912 Germany Jan. 31, 1931 

